Local time goes backwards

I’m getting this from 22Na decays. Any ideas?

G4WT3 >   G4ParticleChange::CheckIt    : the local time goes back  !!  Difference:  3.29998e-06[ns] 
G4WT3 > e- E=0.735626 pos=-1.31298e-06, 0.00349504, 0.371353 global time=1.2135e+17 local time=0.00658129 proper time=0.00231587
G4WT3 >   G4ParticleChange::CheckIt    : the proper time goes back  !!  Difference:  1.35268e-06[ns] 
G4WT3 > e- E=0.735626 pos=-1.31298e-06, 0.00349504, 0.371353 global time=1.2135e+17 local time=0.00658129 proper time=0.00231587
G4WT3 >       -----------------------------------------------
G4WT3 >         G4ParticleChange Information  
G4WT3 >       -----------------------------------------------
G4WT3 >         # of 2ndaries       :                    0
G4WT3 >       -----------------------------------------------
G4WT3 >         Energy Deposit (MeV):                    0
G4WT3 >         Non-ionizing Energy Deposit (MeV):                    0
G4WT3 >         Track Status        :                Alive
G4WT3 >         True Path Length (mm) :            -0.000902
G4WT3 >         Stepping Control      :                    0
G4WT3 >         Mass (GeV)   :                    0
G4WT3 >         Charge (eplus)   :                    0
G4WT3 >         MagneticMoment   :                    0
G4WT3 >                 :  =                    0*[e hbar]/[2 m]
G4WT3 >         Position - x (mm)   :             -0.00182
G4WT3 >         Position - y (mm)   :                 3.49
G4WT3 >         Position - z (mm)   :                  371
G4WT3 >         Time (ns)           :              0.00658
G4WT3 >         Proper Time (ns)    :              0.00231
G4WT3 >         Momentum Direct - x :                0.567
G4WT3 >         Momentum Direct - y :                0.657
G4WT3 >         Momentum Direct - z :                0.496
G4WT3 >         Kinetic Energy (MeV):                0.736
G4WT3 >         Velocity  (/c):                0.912
G4WT3 >         Polarization - x    :                    0
G4WT3 >         Polarization - y    :                    0
G4WT3 >         Polarization - z    :                    0
G4WT3 >         Touchable (pointer) :          0x14a1604e0

Hi John,
you may post this to the Physics Processes Forum and perhaps add more information on how you get that…
Gabriele

Mysteriously the symptom has gone away.